Was a fantastic product. Now it's rubbish if you are an occasional user who needs some broadband use for the odd bit of travel, surfing in a cafe, etc.
I don't need 3G a month, or 1G even. 1G that doesn't expire, ever, was the killer feature for me buying the product under the old T&Cs. I've used it for nearly a year and have only used £2 of my £15 credit! Under the new system I'd be paying £15 a month.
On the technical side, it works fine. Just plug in, install the software and off you go. Even receives SMS messages. The 30 day limit makes the PAYG nature of it worthless though. If you're a heavy user you'd get a contract, if not you wouldn't want this.